Yarn tensioning device



Aug. 5, 1969 WILD] ET AL 3,459,389

YARN TENSIONING DEVICE Filed Feb. 15, 1967 2 Sheets-Sheetl INVENTORS: Edd, Willie BY Baum 8:34.69

Aug. 5, 1969 Y E. WILD! ET AL 3,459,389

YARN TENSIONING DEVICE Filed Feb. 15, 1967 2 Sheets-Sheet 2 i INVENTOR. 4920 MIJT & BY 55min B SQHJF United States Patent O 3,459,389 YARN TENSIONING DEVICE Edwin Wildi, Niederuzwil, and Benno Biscliof, Uzwll, Switzerland, assignors to Maschinenfabrik Benninger A.G., Uzwil, Switzerland, a body corporate of Switzerland Filed Feb. 15, 1967, Ser. No. 616,323 Claims priority, application Switzerland, Feb. 15, 1966, 2,208/66 Int. Cl. B65h 59/22 U.S. Cl. 242-150 7 Claims ABSTRACT OF THE DISCLOSURE A yarn tensioning device encompassing at least an upper and a lower disk between which passes the yarn so as to be tensioned by opposite surfaces of such disks. At least one of these two disks, and typically the lower disk, is positively driven independent of the speed of movement of the yarn, in order to insure that the throughpassing yarn exerts a self-cleaning action upon the opposite disk surfaces, and further, that the tensioning action of these two disks upon the yarn is maintained substantially constant. The invention further contemplates providing a further pair of such disks wherein the lower disk thereof may also be positively driven, and therein the first pair of disks of the two disk pairs serves to steady the yarn which is moving in a substantially linear or straight line path through the yarn tensioning device.

BACKGROUND OF THE INVENTION The present invention relates to an improved yarn tensioning device of the type wherein the yarn passes between an upper and a lower disk and is tensioned by confronting or opposite disk surfaces which exert a more or less pronounced clamping action upon the throughpassing yarn or the like. I

Under the known prior art yarn tensioning devices of this type there are arrangements where both disks are not rotatable, and others where the lower disk or the upper disk, or both disks, are rotatable and can be entrained by the throughpassing yarn.

However, it has been found that the disks of these yarn tensioning devices are subjected to considerable wear owing to the missing or, in any case, inadequate rotation of the same. Furthennore, it has been seen that in these known yarn tensioning devices dirt is quickly accumulated between the disks and thus alters the clamping effect upon the yarn and in any case aifects its uniformity, so

that these prior art yarn tensioning devices always have to be periodically subjected to a cumbersome and timeconsuming cleaning operation.

SUMMARY OF THE INVENTION Accordingly, it is a primary object of the present invention to provide an improved yarn tensioning device which overcomes the drawbacks of the prior art structures mentioned above.

Another, more specific object of the present invention pertain to an improved yarn tensioning device which is not only relatively simple in construction and economical to manufacture, but additionally insures that a substantially uniform tension will be exerted upon the yarn so that the quality of the yarn is not adversely affected.

Still a further significant object of this invention concerns an improved yarn tensioning device which provides for a substantially uniform clamping effect of its disk members upon the yarn so that the uniformity of the yarn is maintained throughout yarn processing, and

ice

wherein the disk members are subjected to a cleaning action to positively prevent any accumulation of dust, dirt or otherwise at the disk members and which would adversely alfect the operation of the yarn tensioning device.

Now, in order to implement these and still further objects of the invention which will become more readily apparent as the description proceeds, and further, in order to prevent the drawbacks of the prior art structures as heretofore mentioned, the inventive yarn tensioning device comprises at least one pair of disks, namely an upper disk and a lower disk between which the yarn passes. According to one very important aspect of the invention, it is contemplated to positively drive at least one of the aforesaid two disks independent of the speed of movement of the yarn, so that the throughpassing yarn continuously and automatically cleans the surfaces of the disks, and therefore, the clamping or tensioning efiect of these disks with respect to the yarn is maintained substantially constant. The continuously rotating disk or disks bring about a continuous, automatic cleaning of the disk surfaces by the yarn itself, the latter of which displaces accumulated dirt against the outer or inner rim of the disk.

In most of the prior art yarn tensioning devices the required tension is achieved by yarn loopings which necessitate complicated threading operations, Particularly in yarn tensioning devices with one disk, where large yarn looping angles are usual, adjustment of the yarn tension is therefore very limited.

Now, these disadvantages can be effectively overcome with the yarn tensioning device according to the present device according to the present invention in that, the yarn is passed in a straight line between the disks, and in order to produce the required yarn tension the upper disk is resiliently pressed against the lower disk.

Many of the known yarn tensioning devices also possess the disadvantage that the yarn may easily come out of engagement with the disks due to the vibrations which are caused when the yarn is unwound from a spool or the like in the immediate vicinity. Furthermore, there are known to the art yarn tensioning devices which are constructed in such a manner that the yarn can easily be caught or snarled thereon.

Yet, these disadvantages can be eifectively prevented with the yarn tensioning device designed according to the teachings of the present invention and which is advantageously a two-disk yarn tensioning device, by protecting the same completely in an upright structural part or member of a bobbin creel having a substantially U-shaped cross-section, and wherein such upright structural member supports further yarn tensioning devices in the same manner. Moreover, in this structural member there are provided oppositely disposed openings for the throughpassage of the yarn and which are aligned in a substantially straight line with respect to another opening or aperture between the two pairs of disks. The first pair of disks, viewed in the direction of advancement or feed of the yarn, serves to steady the yarn.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be better understood, and objects other than those set forth above, will become apparent, when consideration is given to the following detailed description thereof. Such description makes reference to the annexed drawings wherein:

FIGURE 1 schematically illustrates three bobbins or spools arranged above one another of a bobbin creel and provided with the associated yarn tensioning devices of the invention;

FIGURE 2 is a schematic sectional view taken along a horizontal plane through a portion of one row of the bobbin creel and depicting two adjacently arranged bobbins and the associated inventive yarn tensioning devices;

FIGURE 3 is a fragmentary, vertical sectional view of one single yarn tensioning device of the invention;

FIGURE 4 is a fragmentary, sectional view of the yarn tensioning device of FIGURE 3, taken along the line IV-IV thereof, with the adjacent parts of the bobbin creel;

FIGURE 5 is a top plan view of the yarn tensioning device shown in FIGURE 3; and

FIGURE 6 is a scross-sectional view of the yarn tensioning device shown in FIGURE 5, taken through the driving arrangement and substantially along the line VI VI thereof.

DESCRIPTION OF THE PREFERRED EMBODIMENT Now, in order to demonstrate the construction and operation of the exemplary depicted yarn tensioning device, it is assumed that one starts from an arrangement of yarns which are drawn ofi for warping from numerous spools arranged on a warp creel. After each yarn has passed an associated yarn feeler or controller and a yarn tensioning device, they are combined or gathered into a bundle and pass a crossweb reed and a warp reed, so as to be wound off as a band under uniform tension onto a winding drum of a warping machine. Accordingly, the figures only illustrate the components of the creel and the various yarn tensioning devices which are necessary to understand the underlying principles of the present invention.

Continuing, it will be understood that in the creel a plurality of spools are closely arranged in a creel frame in the usual manner, these spools being located above one another in horizontal rows. Specifically, FIGURE 1 illustrates three such spools 1, each of which belongs to a different row, and FIGURE 2 shows two adjacent spools 1 in the same row.

The spindles for the spools 1 can be considered to be well known and since their physical structure is not necessary for an understanding of the invention they are thus not illustrated. The yarn 2, which is wound off each spool 1, is passed through two legs or arms 3a, 3b of a structural member or part 3 of the creel which is in close vicinity to its respective spool 1 and which has a substantially U- shaped cross-section. As clearly illustrated in FIGURE 2, the yarn 2 is deflected from this structural or profile member 3 at almost a right angle to a non-illustrated, conventional winding drum. Between its entry into one leg 3a of the structural member 3 and its exit from the opposite leg or arm 3b of this structural member 3, the yarn 2 passes the associated inventive yarn tensioning device.

Considering now the yarn tensioning device in reater detail, such is mounted on a support or carrier 5 which is constructed in such a manner that a disk wheel 7 and 7a respectively, can be mounted on two identical substantial ly box-shaped bearings 6 and 611, respectively. Each of these disk wheels 7 and 7a carries a damper plate 8 and 8a respectively, which, in turn, each carry a disk 9 and 9a of the yarn tensioning device. These disks 9 and 9a possess a collar 10 and 10a, respectively, extending downwards from the center of the associated disk and through which accumulated dirt can be led away through the openings or apertures 11, 11a of the disk wheel 7, 7a, respectively. Also, the exterior rim of each of the disks 9, 9a is extended downwards, as shown at 12 and 12a, so as to prevent the passing yarn 2 from becoming damaged on projecting edges.

On each of these lower disks 9 and 9a there freely lies a top or upper disk 13 and 13a, respectively, having an exterior upward extending rim 14 and 14a, respectively, and which is located in the support or carrier 5 by means of projecting retaining means or segments 15 (FIGURE 5) of the same in such a manner that the two pairs of disks 9, 13 and 9a, 13a lie approximately centrally on top of one another.

As best seen by referring to FIGURE 5, on those parts of the arms 3a, 3b of the structural member 3 where the yarn 2 enters or leaves and also between the two pairs of disks 9, 13 and 9a, 13a on the carrier 5, there are provided guide openings 16, 17 and 18 for the yarn 2. These guide openings 16, 17 and 18 are aligned in a substantially straight line, so that the yarn 2 or the like is withdrawn in a straight line. This arrangement primarily has the advantage that the yarn 2 can be inserted by a simple and straight threading tool. In addition thereto, the location of the openings 16, 17 and 18 in relation to the pairs of disks 9, 13 and 9a, 13a is chosen in such a manner that the associated yarn 2 cannot unthread.

Beneath each of the carriers or supports 5 for the yarn tensioning device there is mounted an inclined tray 19 or other suitable collecting device in the structural member 3 (FIGURES 1 and 6). Tray 19 leads away accumulated dirt falling through the associated openings or apertures 11 and 11a. In this way the dirt or otherwise is directed outwards over one corner of the structural member, and hence, cannot fall onto a yarn tensioning device located underneath.

Dirt coming from the exterior rim or collars 12, 14 and 12a, 14a of the pairs of disks 9, 13 and 9a, 13a respectively, are also led to the tray 19 through apertures 20 provided in the associated support or carrier 5 (FIG- URE 5). Furthermore, the structural member 3 is constructed in such a manner that its base 21 prevents dust from being brought directly into the yarn tensioning device due to the air current 22 (FIGURE 2) produced by the advancement or feed of the yarn 2.

As FIGURE 4 clearly shows the disk pair 9, 13 is additionally provided with means which enbales the upper disk 13 to press to a greater or lesser degree against the lower disk 9, as required, and thus to increase or decrease the tension of the yarn. In this arrangement the first disk pair 9a, 13a, viewed in the direction of yarn advancement, reduces the vibration of the entering yarn 2 which is withdrawn from the associated spool 1.

The device or mechanism which regulates the tension of the yarn advantageously comprises an axially displaceable rail member 23 which is located between the support or carrier 5 and the structural member or part 3, and such rail member can be adjusted in vertical direction by any suitable non-illustrated means. One angle element 24 is secured to this rail member 23 for each yarn tensioning device. Each such angle element 24 is provided with a pressure pin 25. The bottom end 26 of pressure pin 25 rests upon a substantially conical-shaped central region 27 of the associated upper or top disk 13. This pressure pin 25 is surrounded by a pressure ring 28, the tension of which is adjustable by means of an adjustment ring 29. Now, in order to alter the tension of the yarn the rail member 23 is vertically displaced and, thus, the bottom end 26 of the pressure pin 25 is pressed more firmly or less firmly against the upper disk 13 by means of the angle element 24, the pressure spring 28 and the adjustment ring 29. On the end 26 of the pressure pin 25 there is provided a further disk member 30 which permits the pin 25 to be guided under normal working conditions in such a manner that the end 26 of said pin is always in contact with the cone region or portion 27 of the upper disk 13.

If a knot or a thickened part of the yarn 2 passes the afore'described yarn tensioning device, then the upper disk 13 must move upwards. Immediately afterwards it must return to its normal working position through the action of the pressure pin 25, the pressure spring 28 and the centering disk 30. In order to make this faultlessly pos- Sible this disk 30 is provided at its marginal region with a conical ring 31 by means of which this centering ring 30 is automatically again placed into its correct bearing position through the agency of the projecting segments 15.

The mounting of the pressure pin 25 in the angle member or element 24 is such that this pressure pin 25 together with the centering disk 30 and with the pressure spring 28 can easily be removed, so that the upper disk 13, like the other upper disk 13a, is easily accessible for cleaning and servicing. It is also possible to displace the rail member 23 vertically, so as to raise the bottom end 26 of the pressure pin 25 from the associated upper disk 13. In this position the entire yarn tensioning device only operates through the dead weight of the upper disks 13 and 13a. The characteristics of the pressure spring 28 permits a large range of adjustments for the tension of the yarn and, furthermore, allows a very precise adjustment of the required yarn tension without necessitating a change in the angle of looping. In all set or regulated tensions of the yarn the yarn runs unaltered through the device.

In addition thereto it is possible, by displacing the rail member 23 in vertical direction, to simultaneously adjust all yarn tensioning devices by means of the members 24, 25, 26, 27, 28 which are located along the rail member 23 and above each of the yarn tensioning devices.

The described yarn tensioning device could be operated as hereinbefore explained. However, in such case it would still have the disadvantage, as with other known yarn tensioning devices, that due to the inefficient entrainment of the freely rotating disks, these disks would be subjected to rapid wear. Furthermore, with such operation and owing to the absence of any self-cleaning action upon deposited dirt or the like, or a self-cleaning action which, at best, is still quite faulty, the tensioning effect upon the throughpassing yarn would be very irregular if the surfaces of the disks were not subject to a complicated cleaning operation at short intervals.

However, these disadvantages are effectively overcome in the illustrated yarn tensioning device by the fact that, one or both of the lower disks 9 and 9a are positively rotated independently of the speed of travel of the yarn 2. For this purpose, and as best illustrated in FIGURE 3, the two disk wheels 7 and 7a, and hence, through the agency of the damping disks 8, 811 also the lower disks 9, 9a, are driven by a suitable drive arrangement. This drive arrangement incorporates any suitable non-illustrated drive motor or the like which drives a common driving shaft 33 for all vertically located yarn tensioning devices in the structural member 3. This driving shaft 33 carries driving pinions 32, each of the yarn tensioning devices being operably associated with such a pinion 32. Each pinion 32 meshes with gear means such as spur gears 34, 34a on the circumference of the disk wheels 7, 7a. The drive is of constant speed and operates in such a manner that the lower disks 9, 9a of the yarn tensioning device are rotated in the direction of the arrows A (FIGURE 5'), that is to say, in the direction of advancement or feed of the yarn 2.

Experiments have shown that a constant driven lower disk also insures a constant yarn tension in spite of the continuous change of the diameter of the spool 1. In addition thereto, the continuous rotation of the disks prevents the disk from becoming cut or otherwise damaged by the yarn, which reduces disk wear to a minimum. At the same time the rotating surfaces of the disk pairs are automatically cleaned by the yarn, insuring for a uniform tension effect of the disks on the yarn 2. By lowering the driving shaft 33 all pinions 32 can be simultaneously brought out of mesh with the disk wheels 7, 7a so as to stop driving of the lower disks 9, 9a. The yarn tensioning device may then be used as a conventional two-disk yarn tensioner. Further, the omission of one of the two disk pairs of the illustrated yarn tensioning device allows the same to be used as a one-disk tensioner. These many possibilities make the described yarn tensioning device so universal that it may be used for a large number of yarn sizes and for numerous types of yarn.

A further advantage of the described yarn tensioning device is that the arrangement within the U-shaped structural member or part 3 and the fact that the yarn travels in a substantially straight line prevents the yarn from catching on the yarn tensioning device or on abutments thereof.

In addition thereto, such structural member or part 3 protects all yarn tensioning devices from being damaged, particularly against damage caused by dropping spools. Furthermore, this arrangement also eliminates hand injuries caused by projecting elements.

Finally, the vertical location of the structural member 3 largely prevents dirt from accumulating on the supports or carriers of the yarn tensioning devices, and the dust or the like generated by the friction of the yarn between the disks is removed by the trays 19.

It also should be pointed out that the present yarn tensioning device possesses no rollers or bolts around which the yarn would have to be wound with a larger or smaller looping angle so as to obtain the required tension, entailing all the dangers of catching, unthreading, etc., of such arrangements and requiring complicated threading operations. In comparison therewith, the yarn in the present yarn tensioning device can be easily threaded by means of an elongated tool and without actuating any components.

All yarn tensioning devices can be adjusted during operation, and this adjustment or control of the yarn tension is effected by the exertion of pressure on the center of the upper disk of each yarn tensioning device.

While there is shown and described a present preferred embodiment of the invention, it is to be distinctly understood that the invention is not limited thereto but may be otherwise variously embodied and practiced within the scope of the following claims.

What is claimed is:

1. A yarn tensioning device comprising at least an upper and a lower disk having opposite disk surfaces between which the yarn passes and is tensioned by said opposite disk surfaces, means for positively driving only said lower disk of said two disks independent of the speed of move: ment of the yarn, in order to ensure that the throughpassing yam continuously and automatically cleans said opposite disk surfaces of said upper and lower disks so that the tensioning action of said two disks upon the yarn is maintained substantially constant, a disk wheel and a damping disk mounted on said disk wheel, said lower disk bearing on said disk wheel through the agency of said damping disk, gear means carried by said disk wheel, said driving means including a drive shaft and a pinion mounted at said drive shaft, said pinion being engageable with said gear means.

2. A yarn tensioning device as defined in claim 1 further including an additional pair of upper and lower disks arranged along the path of advancement of the yarn, the first pair of disks lying in the direction of advancement of the yarn serving to steady the yarn, and means for ensuring that the yarn passes in a substantially straight line through both pairs of disks between said upper and lower disk of each pair.

3. A yarn tensioning device as defined in claim 2 wherein said lower driven disk is provided with a central opening bounded by a downwardly extending collar member, said lower driven disk further being provided with a downwardly extending exterior rim portion, a tray arranged beneath said lower driven disk, said central opening and said downwardly extending exterior rirn portion of said lower driven disk serving to lead away accumulated dirt to said tray.

4. A yarn tensioning device as defined in claim 3, further including at least one substantially upright structural member of a bobbin creel having a substantially U-shaped cross-section, said structural member supporting a plurality of pairs of upper and lower disks and serving to protect said pairs of disks.

5. A yarn tensioning device as defined in claim 4 wherein a plurality of said substantially U-shaped upright structural members are provided arranged adjacent one another, the open side of one of said U-shaped structural members facing a closed side of another one of said substantially U-shaped structural members, and wherein said means for ensuring that the yarn passes in a substantially straight line comprises opposite guide openings provided at said substantially upright structural members and means providing a further opening arranged between said two pairs of disks.

6. A yarn tensioning device comprising at least an upper and a lower disk having opposite disk surfaces between which the yarn passes and is tensioned by said opposite disk surfaces, means for positively driving only said lower disk of said two disks independent of the speed of movement of the yarn, in order to ensure that the throughpassing yarn continuously and automatically cleans said opposite disk surfaces of said upper and lower disks so that the tensioning action of said two disks upon the yarn is maintained substantially constant, means for ensuring that the yarn passes in a substantially straight line between said two disks, said upper disk possessing a central region of substantially conical shape, resilient pressing means for resiliently pressing said upper disk against said lower disk so as to tension the yarn, said resilient pressing means including spring means acting upon said central conical region of said upper disk for urging the latter with pressure against said lower disk, said resilient pressing means further including a pressure pin acted upon by said spring means, said pressure pin having an end contacting said conical central region of said upper disk, said yarn tensioning device further including means for retaining said upper and lower disks in a predetermined position relative to one another, a centering disk member having a conical ring carried by said pressure pin, said centering disk member cooperating with said retaining means in order to return said end of said pressure pin into its correct position on the upper disk after said upper disk has been displaced by a thickened portion of the yarn.

7. A yarn tensioning device as defined in claim 6, further including an axially displaceable rail member for carrying said pressure pin, said axially displaceable rail member extending substantially parallel to said pressure pin and enabling the pressure of said upper disk against said lower disk to be controlled during operation of the yarn tensioning device.

References Cited UNITED STATES PATENTS 2,432,696 12/1947 Swanson 242-l 2,457,450 12/1948 Dcwas 242-450 2,629,561 2/1953 Heizer 242l5'0 X 2,661,913 12/1953 Heizer et al. 242 3,297,264 1/1967 Gilbos 242-150 X STANLEY N. GILREATH, Primary Examiner US. Cl. X.R. 242-131 

